yeah ive been reading about them, im VERY electrically inclined. but never dealt with relays.

what makes no scense is why im even talking about all this. the blue RTL is not going to the DCs at all. it has its own two wires coming from the head unit. i assume one is power and the other is signal.

the only possible corrilation is if the blue RTL is split internally on the circuitboard inside the HU and goes to the DCs threw one of its dedicated wires. then the blue RTL would already be split and possibly maxed out amprage wise with the factory amp and DCs. and the second amp and 3rd amprage draw put it over the top with too much draw.